The Coast Guard will collect $4 million from the operator and owner of a barge that exploded in 2003 in the waters off Staten Island, killing two workers and dumping more than 50,000 barrels of unleaded gasoline into the Arthur Kill.

The civil penalty, announced yesterday, is the largest ever collected by the Coast Guard in a federal Clean Water Act case.

The barge’s operator, Bouchard Transportation Co. of Melville, LI, and its owner, the B. No. 125 Corp., agreed to pay the settlement, which is awaiting the approval of a Brooklyn federal judge.